Automatic elevatob-door closer



M. E. LATHAM. AUTOMATIC ELEVATOR DOOR CLOSER. APPLICATION FILED FEB. 24. 1919.

'1 3 1 2, 500, Patented Aug. 5, 1919.

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NI. E. LATHAM.

AUTOMATIC ELEVATOR DOOR CLOSER.

APPLICATION FILED FEB. 24. I919.

Patented Aug". 5, 1919.

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MATTIE E. LATHAM, OF MONTEVALLO, ALABAMA.

AUTOMATIC ELEVATOR-DOOR CLOSER.

Specification of Letters Patent.

Patented Aug. 5, 1919.

Application filed February 24, 1919. Serial No; 278,698.

To all whom it may concern:

Be it known that I, MATTIE E. LATI-IAM, a citizen of the United States, residing at Montevallo, in the county of Shelby and State of Alabama, have invented new and useful Improvements in Automatic Elevator-Door Closers, of which the following is a specification. v

This invention relates to elevators and has for its object the provision of means whereby the door of the elevator-shaft will be automatically closed as the elevator leaves a floor after stopping, this means being entirely independent of any voluntary action by the operator of the car and being designed to prevent accidents which are of such common occurrence.

An important object is the provision of means of this character which is so constructed that the door closing means will be automatically reversed when the elevator reaches the extreme limits of its travel whereby the door closing means will be operative regardless of whether the elevator is ascending or descending.

A further object is the provision of means of this character which will be comparatively simple and inexpensive in manu facture and installation, efficient in use, durable in use, and a general improvement in the art.

With the above and other objects and advantages in view, the invention consists in the details of construction to be hereinafter more fully described and claimed, and illustrated in the accompanying drawings, in which- Figure 1 is a longitudinal section of a portion of an elevator shaft looking toward the door and showing the door thereof equipped with my device,

Fig. 2 is a longitudinal sectional view through the shaft and elevator,

Fig. 3 is an elevation of the elevator showing the coacting means carried thereby,

Fig. 1 is a horizontal sectional view through a portion of the elevator and its control wheel, and

Fig. 5 is a detail perspective view showing the rack bar, its guide and the shifting means carried by the control wheel.

Fig. 6 is a fragmentary detail showing the relation of a rack and pinion when the door is closed.

Referring more particularly to the drawings, the letter A designates an elevator and B designates the elevator shaft pr0- vided with the usual doors C at each landing.

In carrying out my invention I provide adjacent each door opening into the shaft, a pair of spaced gears 10 and 11 which are arranged out of alinement and which are mounted upon suitable shafts 12 and 13 mounted in any preferred bearings. The shafts 12 and 13 have secured thereon pinions 14 and 15, respectively, which mesh with racks 16 and 17, respectively, secured upon the inner face of the door C. The shafts 12 have their bearings rigidly secured upon the front wall of the elevator shaft andthe gears 10 and 11 are disposed in the path of travel of an actuating member carried by the elevator.

- This actuating member is in the nature of a rack 18 mounted upon a dove-tailed slide 19 mounted within a correspondingly shaped guide 20 secured upon the front of the elevator A. The elevator operating wheel is designated by the letter D and has its shaft E provided with a worm 21 engaging a stud 22 on the slide 19 for a purpose to be described.

In the travel of the elevator the rack 18 carried thereby is always in position to engage one of the gears 10 or 11 journaled on the wall of the elevator shaft at each opening. When the operating wheel I) is in position to control the ascent of the elevator, the worm 21 carried by the shaft E of the wheel will cause the slide 19 to be moved into such position that the rack 18 will be projected into such a position that it will engage the gears 10, which of course aline at all the landings. Assuming that the elevator has stopped at a floor, when the elevator ascends from that floor or landing, the rack 18 will engage the gear 10 and rotate the shaft 12 and consequently the pinion 1 1, whereupon this gear and pinion will be rotated in a clockwise direction, the rotary movement of the pinion 14 causing movement of the door to closed position on account of the intermeshing of the teeth of the pinion 14 with the rack 16. It is understod of course that the rack 18 is of sufficient length that it will cause suflicient rotary movement of the gear 10 that the pinion 14 will effect pro er closing of the door. It is also understoo that the door is provided with the usual or any preferred looking or latch means whereby it will be held fast after it is closed. When the door is in closed position passage of the elevator past a floor without stopping will of course effect rotary movement of the gear 10 and pinion 1 1 but the movement of the pinion 1 1- cannot effect theposition of the door as when the door is in closed position the teeth of the rack bar 16 will practically but not quite clear the teeth of the pinion 1-1, that is to say there is a slight clearance at the end of the rack bar 16.

WVhen the elevator reaches the extreme upper limit of its movement and the operator reverses the wheel D, as is the ordinary practice, the engagement of the worm 21 with the stud 22 on the slide 19 will cause the slide 19 to be moved within the guide 20 into such position that the rack 18 will be so disposed that it will be in alinement with the gears 11 at all the different landings. The gears 10 then become entirely inoperative. As the elevator descends and passes each landing the rack 18 will engage the gear 11 and cause rotation of the pinion 15. When the elevator stops at a landing and the door is opened, upon leaving the landing if the operator does not close the door manually, engagement of the rack 18 with the adjacent gear 11 will of course cause rotation of the pinion 15 and by virtue of the engagement of the pinion 15 with the rack 17 will cause the door to be moved to closed position. If the elevator passes a landing without stopping the clearance at the end of the rack bar 17 will permit the pinion 15 to be rotated in a counterclockwise direction without effecting the position of the rack bar 17 From the foregoing description and a study of the drawings it will be apparent that I have provided extremely simple and inexpensive means whereby the door of an elevator shaft will be automatically closed as the elevator leaves a landing entirely without dependence upon voluntary action of the operator of the elevator.

While I have shown and described the preferred embodiment of my invention it is of course to be understood that I reserve the right to make such changes in the form, construction, and arrangement of parts as will not depart from the spirit of the invention 'or the scope of the subjoined claims.

Having thus described my invention, 1 claim 1. In combination with an elevator, an

elevator shaft and the doors thereof, racks of each door, ai'pair of shafts arranged in vertical alinement and journaled upon the shaft adjacent each door opening therein, gears on said shaftsarranged in non-alinement, pinions on said shafts meshing with said racks, a rack carried by the elevator, and means for moving said last named rack whereby said last named rack may be caused to mesh with either of said gears.

3. In combination with an elevator, its shaft, and the doors of the shaft, automatic door closing means comprising a pair of vertically spaced rack bars arranged transversely of and secured upon the inner face of each door, a pair of shafts arranged in vertical alinement and journaled upon the shaft adjacent each door opening therein, gears on said shafts arranged in non-alinement, pinions on said shafts meshing with said racks, a rack carried by the elevator, and means for moving said last named rack whereby said last named rack may be caused to mesh with either of said gears, said means comprising a connection between the control ling wheel of the elevator and said last named rack whereby said last named rack will be shifted from one vertical plane to another to correspond with the positions of said gears upon reversal of the operating wheel.

In testimony whereof I affix my signature MATTIE n. LATHAM.

Copies of this patent may he obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

